Submersible Pump Cable Selection Chart (60 Hz) - Grundfos SP Series Installation And Operating Instructions Manual

7.4 Submersible pump cable selection
chart (60 Hz)
The following tables list the recommended
copper cable sizes and various cable lengths for
submersible pump motors.
These tables comply with the 1978 edition of the
National Electric Table 310-16, Column 2 for
167 °F (75 °C) wire. The ampacity (current
carrying properties of a conductor) have been
divided by 1.25 per the N.E.C., Article 430-22, for
motor branch circuits based on motor amps at
rated horsepower.
To assure adequate starting torque, the maximum
cable lengths are calculated to maintain 95 % of
the service entrance voltage at the motor when
the motor is running at maximum nameplate
amps. Cable sizes larger than specified may
always be used and will reduce power usage.
The use of cables smaller than the
recommended sizes will void the
warranty. Smaller cable sizes will
Caution
cause reduced starting torque and
poor motor operation.
Volts Hp
14
.33 130
115
.5 100
.33 550
.5 400
.75 300
1 250
1.5 190
230
2 150
3 120
5
7.5
10
Notes:
1. If aluminum conductor is used, multiply lengths by 0.5. Maximum allowable length of aluminum is
considerably shorter than copper wire of same size.
2. The portion of the total cable which is between the service entrance and a 3Ø motor starter should
not exceed 25 % of the total maximum length to assure reliable starter operation. Single-phase
control boxes may be connected at any point of the total cable length.
3. Cables #14 to #0000 are AWG sizes, and 250 to 300 are MCM sizes.
Single-phase motor maximum cable length [ft]
(Motor to service entrance) (2)
12 10 8 6
210 340 540 840
160 250 390 620
880 1390 2190 3400
650 1020 1610 2510
480 760 1200 1870
400 630 990 1540
310 480 770 1200
250 390 620 970
190 300 470 750
180 280 450
200 310
250
Wire size
4 2 0 00
1300 1960 2910
960 1460 2160
5250 7960
3880 5880
2890 4370 6470
2380 3610 5360 6520
1870 2850 4280 5240
1530 2360 3620 4480
1190 1850 2890 3610
710 1110 1740 2170
490 750 1140 1410
390 600 930 1160
000 0000 250 300
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